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1.
A hitherto unknown hydroxy acid has been isolated from Blepharis sindica seed oil has been characterized as 9-hydroxydodecanoic acid by IR, NMR and mass spectral studies. The structure of this acid was further supported by its chemical transformations.  相似文献   

2.
3-Indole carboxylic acid (ICA) has been characterized as an endogenous constituent of Pinus sylvestris needles. Quantitative estimates of 3-indole acetic acid (IAA) and ICA, corrected for both sample losses and the conversion of IAA to ICA occurring during purification, indicate that Pinus needles contain 24.5 ± 6.5 ng IAA/g and 2.3 ± 0.4 ng ICA/g.  相似文献   

3.
The structure of terminic acid, a new dihydroxytriterpene carboxylic acid isolated from the roots of Terminalia arjuna, has been established as 3β, 13β-dihydroxylup-20(29)-en-28-oic acid by a study of its chemical reactions and spectroscopic data. Terminic acid and its derivatives were found to undergo skeletal rearrangement under protonic conditions to yield oleanene lactone.  相似文献   

4.
Urea carboxylic acids, products of aryl hydantoin hydrolysis, were recently identified as a new antischistosomal chemotype. We now describe a baseline structure–activity relationship (SAR) for this compound series. With one exception, analogs of lead urea carboxylic acid 2 were quite polar with Log?D7.4 values ranging from ?1.9 to 1.8, had high aqueous solubilities in the range of 25–100?µg/mL, and were metabolically stable. None of the compounds had measurable in vitro antischistosomal activity or cytotoxicity, but four of these had moderate worm burden reduction (WBR) values of 42–70% when they were administered as single 100?mg/kg oral doses to S. mansoni-infected mice. These data indicate that with the exception of the gem-dimethyl substructure and the distal nitrogen atom of the urea functional group, the rest of the structure of 2 is required for in vivo antischistosomal activity.  相似文献   

5.
A new triterpene acid, rubinic acid, was isolated from the chloroform extract of the leaves of Rubus fruticosus. On the basis of physical methods and chemical degradation experiments, its structure was determined as 7α-hydroxyursonic acid.  相似文献   

6.
A new triterpene acid, rubitic acid was isolated from the alcoholic extract of the whole plant of Rubus fruticosus. On the basis of physical methods coupled with chemical investigations, the structure of rubitic acid was shown to be 7α-hydroxy ursolic acid.  相似文献   

7.
A fatty acid, found as a minor component in the seed oil of Baliospermum axillare, is shown to be the hitherto unknown 11,13-dihydroxytetracos-trans-9-enoic acid (axillarenic acid).  相似文献   

8.
A new isomer of ricinoleic acid has been found as a minor constituent (1.5%) of the seed oil of Plantago major. This previously unknown β-hydroxyolefinic acid, 9-hydroxy-cis-11-octadecenoic, was characterized by IR, 1H NMR and oxidative cleavage, and the structure was supported by MS.  相似文献   

9.
Cestric acid, a new phenolic ester was isolated from leaves of Cestrum euanthes. By means of GC, HPLC, mass spectroscopy, GC/MS, and 13C NMR, it was shown to be an ester of caffeic acid with glucaric acid. The ester occurs as an equilibrium mixture of four isomers.  相似文献   

10.
The seed oil of Peganum harmala contains a previously unknown dihydroxy acid characterised as 9,14-dihydroxy octadecanoic acid. P. harmala is the first higher plant found to contain this non-vicinal diol acid (3.2%) in its triglycerides.  相似文献   

11.
Thirteen new labdane-type diterpenes have been isolated from the seeds of Sciadopitys verticillata together with six known ones, sciadin, sciadinone, dimethyl sciadinonate, lambertianic acid and its methyl ester and trans-communic acid. Their structures have been determined by chemical and spectral methods.  相似文献   

12.
A fatty acid, found as a minor component in the seed oil of Mirabilis jalapa, is shown to be the hitherto unknown 8-hydroxyoctadeca-cis-11,14-dienoic acid.  相似文献   

13.
Poilaneic acid, a cembranoid diterpene from Croton poilanei, has been characterized as (1R*,2E,4Z,7E, 11Z)-12-carboxyl-1-isopropyl-4,8-dimethylcyclotetradecatetraene.  相似文献   

14.
Three new ursene carboxylic acids, uncaric acid, diketouncaric acid and diacetyluncaric acid were isolated from the woody part of Uncaria thwaitesii, interrelated and their structures established.  相似文献   

15.
Levels of uric acid in the whole body of the tobacco hornworm, Manduca sexta increased steadily for the 9 days of the fifth instar. However, concentrations in the haemolymph were lowest during the transition from the feeding stage to the wandering stage (days 3, 4), the time when there was a switch from uric acid excretion by the Malpighian tubule-hindgut system to storage in the fat body. Haemolymph volumes, determined for larvae between 2 and 6 days into the fifth instar by isotope dilution with [14C]-inulin, were used to calculate rates of incorporation of uric acid into Malpighian tubules and fat body of larvae injected with [14C]-uric acid. These labelling studies indicated that the Malpighian tubules ceased to remove uric acid from the haemolymph some time between the last 6 hr of day 3 of the fifth instar and the first 18 hr of day 4. At the same period, fat body removed significant quantities of uric acid from the haemolymph. The times of initial decreases and increases in levels of uric acid in haemolymph and fat body, respectively, indicated that storage in the fat body started before cessation of elimination via the Malpighian tubule-hindgut system.  相似文献   

16.
The structure of a unique lignan diester from Salvia plebeia seed has been determined. Hydrolysis of the diester yields ferulic acid, (+)-l2 l-methyltetradecanoic acid and secoisolariciresinol.  相似文献   

17.
Reduced polypeptide subunits of α-, β- and γ-conglutins from Lupinus angustifolius seeds were resolved by preparative SDS gel electrophoresis of the fluorescent labelled proteins, into four, six and two major components, respectively. All subunits were glycosylated, to varying degrees, containing mannose, galactose and glucosamine. The major glycopeptides released by pronase digestion of each conglutin had similar galactose/mannose ratios; the MW of the glycopeptide released from α- and β-conglutin was ca 5000. Although on average, each molecule of α-conglutin contains one main oligosaccharide chain, and β-conglutin two, the presence of carbohydrate in all polypeptide subunits suggests that some subunits may arise by proteolytic cleavage of a larger polypeptide after glycosylation. The presence of minor glycopeptide components indicates that modification of carbohydrate chains during seed development may also occur.  相似文献   

18.
The seed globulins of Lupinus albus were extracted and 12 ditterent proteins were separated: four of them correspond to vicilins and two to legumin  相似文献   

19.
A new pentacyclic triterpene acid was isolated from the arial parts of Salvia virgata and its constitution was established as 3β-hydroxy-1-oxo-olean-12-en-28-oic acid and named virgatic acid.  相似文献   

20.
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